CHEMICAL COMPOSITION AND FEEDING VALUE OF GRASS ANDFORAGE CROPS

摘要

More than a century ago. researchers were already interested to understand and to describe the quality of forage for cattle. The problem was "How to determine the quality of a specified forage for ruminants by the chemical analysis of a small sample ?". Not only for the food industry but also for the improvement and breeding of forage crops the indication of effective quality parameters would be a great helpFor the farmer himself it would be a good help to adjust the rations for his animals to their milk and meat production capacity Most methods were developed empirically whereby temperature. pH, time, highly influenced the resultThe precise description of the method is necessary to interpret the results (e.g. crude protein, crude fibre, digestibility) The most applied are the Weende and Van Soest methods,together with the digestibility "in vitro technique developed by Tilley and TerryDuring the last decennia also non destructive methods, like the Near Infrared Reflectance Spectroscopy NIRS are used more frequently.Fast and reliable non destructive methods are more attractive and acceptable than laborious, polluting and animal unfriendly ones. Forages contain a lot of quality parameters (protein, fat. Isugars, structural carbohydrates, vitamins, but some of themcontain also anti quality components (alkaloids nitrates).The diet of domestic ruminants is composed of more than 1 component like tgrassOther diet components may interfere and mostly result in a synergism the combination of protein rich forage (legumes) with starch riche ones results often in better animal productions than given as sole diet components